Trident Asset Management, L.L.C. They are sabotaging my credit, and stopping other companies from doing business with me Alpharetta, Georgia

I began to notice that my checks were not being accepted around town in Lakeland, Florida.
I was stumped?  I did further research and found that the collection company Trident Asset L.L.C had purchased a bogus unpaid check that was stopped in October of 2009 because I did not continue to purchase a washer from Best Buy.  Best Buy assured me the check was destroyed the next day since the purchase was cancelled, as well as my check, and no product was delivered.
Since I could not figure out at the time why my credit was being destroyed I began to pay Trident in small amounts to repair my credit.  Trident said they would remove the report to other companies that my checks were good to accept as payment.  
When I found proof that I never purchased a washer from Best Buy, Trident still wanted payment to stop other stores from refusing to take my checks due to my legal stoppage of a check to Best Buy for a stopped purchase of a washing machine in 2009.  
I just want my good name cleared from their collection company that purchases debt without proper research from other companies, to collect by brute fear of destroying your credit and having the power to stop your checks from being accepted from major companies like Walmart, Home Depot, and Best Buy.  This Trident Company needs to do more research to ensure the debt they are purchasing is real before they ruin an individuals credit to the point your checks are not accepted by other companies!  
I am on Social Security Disability in a wheel chair, and was only given 30 days after a letter was sent in March 2012, and after my credit was impacted by them negatively to prove this debt was invalid from 2009.  This is a very poor way to make a profit from an individual, especially a person who is disabled and unable to defend themselves within 30 days, and after a negative report is already dispatched all over to other companies not to accept your checks!  Who can help me stop this abuse of the collection system in the United States of America?